Frequently asked questions
Q1 What is Energy from Waste (EfW)?
EfW includes a range of technologies used for converting the waste left after recycling into electricity and heat. Although it is often used to refer to combustion of residual municipal solid waste, the term includes any process that uses waste as a fuel to generate energy.
An EfW facility using combustion involves burning residual waste at high temperatures without the addition of any extra fuel, and under controlled conditions. Emissions are cleaned to meet rigorous air quality standards before being released into the atmosphere. Heat from the combustion process is used to produce steam, which drives a turbine to generate electricity. Heat can also be recycled to provide low pressure steam, hot water, space heating or even refrigeration for use in industrial or domestic buildings.
Q2 Is EfW just another name for incineration?
EfW is more than just incineration. The sole purpose of an old-style incinerator was to dispose of unwanted materials by burning them. A modern EfW via combustion faclity is a power plant that uses the thermal treatment process to generate electricity and heat. It extensively cleans up the combustion gases before emission to the atmosphere and involves post-combustion extraction of metals and reuse of ash.
Q3 What are the benefits of EfW?
EfW includes proven and reliable technologies. It allows recovery of value in the form of heat energy and recycled materials as resources that would otherwise be wasted. EfW can help prevent a UK energy deficit as it is reliable and secure. It can also help to reduce greenhouse gas emissions.
Q4 What is the UK track record for EfW?
EfW technologies are proven and reliable technologies which are currently used in the UK by many local authorities. There are 24 EfW facilities located in both urban and rural areas. There is huge potential in the UK to increase EfW to provide energy and achieve more sustainable waste management.
Q5 Do EfW facilities discourage recycling?
Even with the expected improvements in recycling rates, there will always be waste materials that cannot be viably recycled. We do not have the technical ability to process all wastes into new products and not every potentially recyclable material has a reuse application. Recycled materials can become so contaminated that they cannot be economically or practically recovered.
There are many examples of EfW operating alongside high levels of recycling. For example, Flanders in Belgium has high levels of waste prevention, reuse and recycling, with around 25% of waste being used for energy generation at EfW plants.
Q6 Is an Environmental Permit needed to operate an EfW facility?
EfW facilities are required to meet strict emissions standards under the European Union (EU) Waste Incineration Directive (WID). All EfW facilities need an Environmental Permit from the Environment Agency to operate. The permit controls all operations and will only be granted if the Environment Agency is sure there will be no adverse effects on the local community and environment.
Q7 Do the EfW facilities affect air quality?
EfW facilities are fitted with advanced technologies that control and monitor emissions. A major part of the plant infrastructure is the air pollution control technology. The extent of 24 hour a day air emission control technology coupled with stringent environmental regulations means EfW facilities are designed and operated to have no significant impact on air quality or health.
As part of any EfW planning application, an Air Quality Assessment will be carried out to look at existing air quality, the potential impact of the facility and associated traffic on local air quality and any mitigation measures.
Q8 What about dioxins?
Dioxins and furans can be produced whenever something is burned, such as cigarettes, barbeques, garden bonfires, industrial furnaces or accidental fires. The burning of residual waste in an EfW plant makes only a very small contribution to existing background levels of dioxins in our environment. Data demonstrates that implementation of stringent regulations for EfW facilities in the USA and the EU have resulted in over a 99% reduction in dioxin emissions compared to emissions in 1990.
Q9 Do EfW facilities smell and are they noisy?
Waste is processed within an enclosed environment with air extraction systems, filters and sound proofing to contain odours and noise. No sorting or treatment of waste takes place in the open. Odour is managed by drawing air through the waste reception hall into the combustion process to ensure that the hall remains uder a negative pressure. This prevents any odours from escaping.
Q10 Is it true that people living near EfW facilities have a higher chance of developing cancer?
There is no scientific peer reviewed evidence to support this claim. No study into the health of communities living near EfW (EfW) facilities has been able to demonstrate a conclusive link between emissions from an EfW facility and adverse effects on public health. A 2004 UK Government report which considered 23 reputable studies and 4 review papers into the patterns of disease around EfW facilities concluded that the risk of cancer caused by living near an EfW facility is so remote that it is too low to measure.
Q11 What happens to the ash produced?
An EfW facility typically produces two types of solid by-products. These are Incinerator Bottom Ash (IBA) and Air Pollution Control (APC) residues. The IBA represents about 25% by weight of the waste. Recyclable materials, such as metals, are easily removed from IBA. The remaining IBA is normally aged and processed. It can then be used as aggregate in civil engineering applications. The quantity of APC residues produced is much lower, typically about 4% of the waste processed by the facility. APC residues are hazardous waste, primarily because they are highly alkaline due to high lime content. APC residues are disposed of at specialist hazardous waste facilities.
Q12 What about the carbon emissions from EfW facilities?
As with any combustion process, burning waste in an EfW facility generates carbon dioxide. However given the composition of the waste a significant proportion of the carbon dioxide is from biogenic sources rather than fossil fuels.
It is, therefore, estimated that for every tonne of waste combusted in modern EfW plants, over 460kg less of carbon dioxide equivalent is released into the air due to avoided methane from landfilling, fossil fuel power generation, and metals production.
DEFRA's Waste and Resources Assessment Tool for the Environment (WRATE) can calculate the environmental impacts of different municipal waste management systems. It uses life cycle assessment to include the resources used, waste transportation and operation of a whole range of waste management processes with their environmental costs and benefits.